Why Kubernetes Security
In August 2023, Kubernetes clusters belonging to over 350 organizations, including large Fortune 500 companies, were found to be unsecured and accessible to the public due to two misconfigurations. In January 2024, a misunderstanding of user access permission groups within Google Kubernetes Engine created a security loophole that potentially exposed millions of containers to any user with a Google Account.
These publicized security risks underscore the importance of creating a holistic Kubernetes security strategy. Such a strategy needs to encompass application security, network security, cloud security and data security. However securing Kubernetes environments is challenging due to various factors, ranging from flat network structures to lack of domain-specific expertise.
As a result, container escape risks can result in a compromised host system. This can disrupt other containers and potentially allow attackers to deploy malware and deactivate security features. Additionally, privilege escalation within the cluster can lead to administrative access over the Kubernetes API server, compromising all workloads and data. It might also lead to broader, and riskier, cloud infrastructure access.
In this blog post, we list 12 best practices for securing Kubernetes that will help you ensure the security and resilience of your environments. This blog post is based on a more detailed ebook, which explains K8s risks, security best practices with examples and open-source tools that you can easily use.
12 Kubernetes Security Best Practices (partial list)
1. Map Resources and Dependencies
Start by creating an inventory of all your Kubernetes assets and the dependencies between them, so you can identify vulnerabilities and attack vectors.
Take into account:
- Pods
- Services
- Namespaces
- Nodes
2. Scan, Validate and Mitigate Container Exposures
Scan container images for vulnerabilities throughout the various phases of the development lifecycle:
- Source code static analysis
- Dependency scanning
- CI/CD integrations
- Runtime scanning and monitoring
- Configuration management
3. Protect etcd
etcd is the key-value store used by Kubernetes for all cluster data, which holds critical operational information. Implement TLS, firewalls and encryption to protect the information and prevent unauthorized access.
4. Secure and Monitor Microservices Traffic
Use mTLS (mutual TLS) to secure inter-service communication. This will ensure both the client and server authenticate each other before any data is exchanged.
5. Implement Network Policies and Segmentation
Control traffic between pods and clusters/nodes with network policies. This will minimize the impact of a compromised pod, preventing lateral movement and privilege escalation.
6. Continuously Automate Red Teaming
Take an adversarial approach to digitally testing the organization. This offensive approach will allow you to detect and mitigate potential security threats in real-time, ensuring that defenses are constantly being fortified and bolstering the overall resilience of your Kubernetes environments. Read more here.
Best Practices
Implementing the security practices above allows DevSecOps and security teams to ensure continuous Kubernetes security, without the noise and while validating exposures. To read more details about each practice, including examples you can read the entire ebook. It also includes more information on the challenges of container escape security and a list of tools you can implement and use to implement these practices.
